Your old phone can be installed in your car using a suction-cup mount and used as a permanent GPS navigation device. Several apps in the iTunes store will give you turn-by-turn directions out loud, but you'll need to be sure that you buy an app that includes map data. An app that depends on a network connection will be of little use when you're on the open road, away from Wi-Fi. TomTom's app has been well-reviewed, and its telltale file-size (1.3 GB) indicates that it comes with all its own maps.